NOT ABLE TO MAKE ANY CHANGES

Hello. I have been using your Accordion Plugin on my website mentioned below. We use it to list our Stores in cities in accordion format. We recently opened a new store and wished to add the new store details. However, the plugin fails to open. If i click on 'Accordion' or 'New Accordion' link on LHS under 'Accordions Tab', it simply OPENS A BLACK NEW TAB and fails to display anything. Its a Blank screen. I tried to delete and re-install the plugin but same issue. Kindly help.